Transgenerational epigenetic inheritance: Emerging concepts and future prospects

Evidence for transgenerational epigenetic inheritance has accumulated in recent years. However, the perceived implausibilities of epigenetic memory survival across chromatin remodeling and reprogramming, and phenotypic information transfer from soma to germline have caused skepticism about its existence, especially in mammals. Importantly, these supposed fundamental impediments seem to be disappearing with recent advances. Evolutionary significance of epigenetic inheritance is another area of debate. Notably, the idea that induced variations may play a role in evolution is gaining ground with newer analysis. Overall, emerging concepts are increasingly calling for integration of nongenetic inheritance in the contemporary evolutionary theory that does not completely explain heritability of complex traits and diseases. Interestingly, a conceptual framework of “evolutionary transgenerational systems biology” has recently been proposed to integrate epigenetics and physiology with inheritance and evolution. A proof of concept analysis is warranted to test the future prospects of this unified theory of biology.